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Old September 29th 06, 04:38 PM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

Jay in the Mojave wrote:
What is the harmonic content with your amp?
Do you have a filter in the output circuit?


Jay, the harmonic content is specified in the brochure at
http://www.telstar-electronics.com/SkyWave%202879AB.pdf
But Frank probably doesn't believe that either... LOL

P.S. No output filtering at this time.

www.telstar-electronics.com

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Old September 29th 06, 05:20 PM posted to rec.radio.cb
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On 29 Sep 2006 08:38:40 -0700, "Telstar Electronics"
wrote in
.com:

Jay in the Mojave wrote:
What is the harmonic content with your amp?
Do you have a filter in the output circuit?


Jay, the harmonic content is specified in the brochure at
http://www.telstar-electronics.com/SkyWave%202879AB.pdf
But Frank probably doesn't believe that either... LOL



You measured output power with a spectrum analyzer, so why should I
believe that you measured harmonic distortion with anything more than
a wattmeter? Of course I don't believe you, Brian; you haven't made a
single verifiable claim regarding any of your amps. In fact, I can
guarantee that your 516 watt PEP figure was never measured but only
fabricated (what you call 'estimated', just like you 'estimated' the
distortion figures on your previous Class C splatter-boxes).


P.S. No output filtering at this time.



Never had it, never will.


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Old September 29th 06, 05:49 PM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

Frank Gilliland wrote:
You measured output power with a spectrum analyzer, so why should I
believe that you measured harmonic distortion with anything more than
a wattmeter? Of course I don't believe you, Brian; you haven't made a
single verifiable claim regarding any of your amps. In fact, I can
guarantee that your 516 watt PEP figure was never measured but only
fabricated (what you call 'estimated', just like you 'estimated' the
distortion figures on your previous Class C splatter-boxes).


I think everyone here who has read has this entire thread has figured
out by now:
You have never used a spectrum analyzer
Don't know what PEP power is
Don't understand how to measure efficiency
Don't know how to measure harmonics

I can't wait to see your new amplifier... LOL


www.telstar-electronics.com

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Old September 29th 06, 11:43 PM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

On 29 Sep 2006 09:49:48 -0700, "Telstar Electronics"
wrote in
.com:

Frank Gilliland wrote:
You measured output power with a spectrum analyzer, so why should I
believe that you measured harmonic distortion with anything more than
a wattmeter? Of course I don't believe you, Brian; you haven't made a
single verifiable claim regarding any of your amps. In fact, I can
guarantee that your 516 watt PEP figure was never measured but only
fabricated (what you call 'estimated', just like you 'estimated' the
distortion figures on your previous Class C splatter-boxes).


I think everyone here who has read has this entire thread has figured
out by now:
You have never used a spectrum analyzer
Don't know what PEP power is
Don't understand how to measure efficiency
Don't know how to measure harmonics

I can't wait to see your new amplifier... LOL



Since you still can't address the issues, once again I will address
them for you:

The PEP to carrier ratio of 4 to 1 presumes a linear response. The
problem is that these transistors (operating above 100 watts PEP; or,
more specifically, your "1dB compression point") are not only horribly
NON-linear, but you will be pushing them into saturation way before
reaching your fabricated figure of 516 watts PEP. Don't believe me?
Crank up your amp and try it. Pump in enough carrier to bring the
output to 129 watts then modulate at 100%. I doubt it will even reach
400 watts PEP, and I have -no- doubt that the harmonic content will be
absolutely horrendous.

I also have no doubt that the amp won't last ten seconds under these
conditions because the thermal resistance of the heat sink that is
required to operate at this power is -0.26 degrees C/W.... and yes,
that's a NEGATIVE number which means you need ACTIVE cooling, and a
lot of it!!!

See what happens when you refuse to do the math? You end up proving
that you have don't have the engineering background to build even a
-CHEAP- CB amp....."LOL"!!!



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Old September 29th 06, 11:44 PM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

On Fri, 29 Sep 2006 02:03:34 GMT, "U-Know-Who"
wrote:


516 watts PEP, huh? You are ignorant.

http://www.telstar-electronics.com/SkyWave%202879AB.pdf


According to his own graph the output power levels off at about
slightly above 155 watts. Assume 165 watts.

This in reality means that a 100% single tone modulated AM signal
can reach PEP values of around 165 watts. So that his amp should be
rated around 40 watts carrier on AM and around 160 watts PEP on
sideband.


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Old September 30th 06, 12:50 AM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

On 29 Sep 2006 16:24:06 -0700, "Telstar Electronics"
wrote:

wrote:
This in reality means that a 100% single tone modulated AM signal
can reach PEP values of around 165 watts. So that his amp should be
rated around 40 watts carrier on AM and around 160 watts PEP on
sideband.


In properly-adjusted AM, average power at 100% modulation = 1.5 X
resting carrier power, and PEP = 4 X resting carrier power

This was taken from http://www.ab4oj.com/peptest.html

which also agrees with
http://www.rf-amplifiers.com/index.php?topic=peak_power

Nice try...

www.telstar-electronics.com


You are doing the math backwards.

You must take the maximum power the amp can deliver before saturation.
That will be your approximate PEP rating. Then divide that figure by
four to get the approximate carrier level for AM.

You are determining the max output and then just assuming that you
can multiply that by four to get the PEP rating. (129 x 4 = 516) It
doesn't work that way.
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Old September 30th 06, 01:04 AM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...


"Telstar Electronics" wrote in message
ups.com...
Frank Gilliland wrote:
Yep, their 'definition' is right on the money.


Want to refute my 516W PEP figure any more?... LOL


That's theoretical, based on maximums, and you know this amp is not capable
of that. In real life, and with the components involved, it will not happen.


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Old September 30th 06, 01:14 AM posted to rec.radio.cb
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Default Look at what Griffey thinks his amp will do...


wrote in message
...
On 29 Sep 2006 16:24:06 -0700, "Telstar Electronics"
wrote:

wrote:
This in reality means that a 100% single tone modulated AM signal
can reach PEP values of around 165 watts. So that his amp should be
rated around 40 watts carrier on AM and around 160 watts PEP on
sideband.


In properly-adjusted AM, average power at 100% modulation = 1.5 X
resting carrier power, and PEP = 4 X resting carrier power

This was taken from http://www.ab4oj.com/peptest.html

which also agrees with
http://www.rf-amplifiers.com/index.php?topic=peak_power

Nice try...

www.telstar-electronics.com


You are doing the math backwards.

You must take the maximum power the amp can deliver before saturation.
That will be your approximate PEP rating. Then divide that figure by
four to get the approximate carrier level for AM.

You are determining the max output and then just assuming that you
can multiply that by four to get the PEP rating. (129 x 4 = 516) It
doesn't work that way.


Oh my! Reality strikes again. But then again, only to those of us who live
in the real world. Some live in a calculated world.


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Old September 30th 06, 02:06 AM posted to rec.radio.amateur.equipment,rec.radio.amateur.homebrew,rec.radio.amateur.policy,rec.radio.cb
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Default Look at what Griffey thinks his amp will do...

U-Know-Who wrote:
"U-Know-Who" wrote in message

tomm way are you enaged in more of the crossposting you claim to hate

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